字段加密的问题

就用md5(password)好了,
比效用md5後的字串比較

import java.security.*;
public class MD5_ok { public final static String MD5(String s) {
  char hexDigits[] = { '0', '1', '2', '3', '4', '5', '6', '7', '8', '9',
    'a', 'b', 'c', 'd', 'e', 'f' };
  try {
   byte[] strTemp = s.getBytes();
   MessageDigest mdTemp = MessageDigest.getInstance("MD5");
   mdTemp.update(strTemp);
   byte[] md = mdTemp.digest();
   int j = md.length;
   char str[] = new char[j * 2];
   int k = 0;
   for (int i = 0; i < j; i++) {
    byte byte0 = md[i];
    str[k++] = hexDigits[byte0 >>> 4 & 0xf];
    str[k++] = hexDigits[byte0 & 0xf];
   }
   return new String(str);
  } catch (Exception e) {
   return null;
  }
} public static void main(String[] args) {
  // MD5_Test aa = new MD5_Test();  System.out.print(MD5_ok.MD5("gg"));
}
}

给你一个加密类,我们自己写的:
package *.*.util.encrypt;public class DesEncrypt {
  public DesEncrypt() {
  }
  final static boolean ENCRYPT = false;   //加密参数
  final static boolean DECRYPT = true;    //解密参数  private static byte SubKey[][][] = new byte[2][16][48]; // 16圈子密钥
  private static boolean Is3DES; // 3次DES标志
  private static byte Tmp[] = new byte[256];
  private static byte deskey[] = new byte[16];  // initial permutation IP
  final static byte IP_Table[] = {
      58, 50, 42, 34, 26, 18, 10, 2, 60, 52, 44, 36, 28, 20, 12, 4,
      62, 54, 46, 38, 30, 22, 14, 6, 64, 56, 48, 40, 32, 24, 16, 8,
      57, 49, 41, 33, 25, 17, 9, 1, 59, 51, 43, 35, 27, 19, 11, 3,
      61, 53, 45, 37, 29, 21, 13, 5, 63, 55, 47, 39, 31, 23, 15, 7
  };
  // final permutation IP^-1
  final static byte IPR_Table[] = {
      40, 8, 48, 16, 56, 24, 64, 32, 39, 7, 47, 15, 55, 23, 63, 31,
      38, 6, 46, 14, 54, 22, 62, 30, 37, 5, 45, 13, 53, 21, 61, 29,
      36, 4, 44, 12, 52, 20, 60, 28, 35, 3, 43, 11, 51, 19, 59, 27,
      34, 2, 42, 10, 50, 18, 58, 26, 33, 1, 41, 9, 49, 17, 57, 25
  };
  // expansion operation matrix
  final static byte E_Table[] = {
      32, 1, 2, 3, 4, 5, 4, 5, 6, 7, 8, 9,
      8, 9, 10, 11, 12, 13, 12, 13, 14, 15, 16, 17,
      16, 17, 18, 19, 20, 21, 20, 21, 22, 23, 24, 25,
      24, 25, 26, 27, 28, 29, 28, 29, 30, 31, 32, 1
  };
  // 32-bit permutation function P used on the output of the S-boxes
  final static byte P_Table[] = {
      16, 7, 20, 21, 29, 12, 28, 17, 1, 15, 23, 26, 5, 18, 31, 10,
      2, 8, 24, 14, 32, 27, 3, 9, 19, 13, 30, 6, 22, 11, 4, 25
  };
  // permuted choice table (key)
  final static byte PC1_Table[] = {
      57, 49, 41, 33, 25, 17, 9, 1, 58, 50, 42, 34, 26, 18,
      10, 2, 59, 51, 43, 35, 27, 19, 11, 3, 60, 52, 44, 36,
      63, 55, 47, 39, 31, 23, 15, 7, 62, 54, 46, 38, 30, 22,
      14, 6, 61, 53, 45, 37, 29, 21, 13, 5, 28, 20, 12, 4
  };
  // permuted choice key (table)
  final static byte PC2_Table[] = {
      14, 17, 11, 24, 1, 5, 3, 28, 15, 6, 21, 10,
      23, 19, 12, 4, 26, 8, 16, 7, 27, 20, 13, 2,
      41, 52, 31, 37, 47, 55, 30, 40, 51, 45, 33, 48,
      44, 49, 39, 56, 34, 53, 46, 42, 50, 36, 29, 32
  };
  // number left rotations of pc1
  final static byte LOOP_Table[] = {
      1, 1, 2, 2, 2, 2, 2, 2, 1, 2, 2, 2, 2, 2, 2, 1
  };
  // The (in)famous S-boxes
  final static byte S_Box[][][] = {
      // S1
      {{14, 4, 13, 1, 2, 15, 11, 8, 3, 10, 6, 12, 5, 9, 0, 7},
       {0, 15, 7, 4, 14, 2, 13, 1, 10, 6, 12, 11, 9, 5, 3, 8},
       {4, 1, 14, 8, 13, 6, 2, 11, 15, 12, 9, 7, 3, 10, 5, 0},
       {15, 12, 8, 2, 4, 9, 1, 7, 5, 11, 3, 14, 10, 0, 6, 13}},
      // S2
      {{15, 1, 8, 14, 6, 11, 3, 4, 9, 7, 2, 13, 12, 0, 5, 10},
       {3, 13, 4, 7, 15, 2, 8, 14, 12, 0, 1, 10, 6, 9, 11, 5},
       {0, 14, 7, 11, 10, 4, 13, 1, 5, 8, 12, 6, 9, 3, 2, 15},
       {13, 8, 10, 1, 3, 15, 4, 2, 11, 6, 7, 12, 0, 5, 14, 9}},
      // S3
      {{10, 0, 9, 14, 6, 3, 15, 5, 1, 13, 12, 7, 11, 4, 2, 8},
       {13, 7, 0, 9, 3, 4, 6, 10, 2, 8, 5, 14, 12, 11, 15, 1},
       {13, 6, 4, 9, 8, 15, 3, 0, 11, 1, 2, 12, 5, 10, 14, 7},
       {1, 10, 13, 0, 6, 9, 8, 7, 4, 15, 14, 3, 11, 5, 2, 12}},
      // S4
      {{7, 13, 14, 3, 0, 6, 9, 10, 1, 2, 8, 5, 11, 12, 4, 15},
       {13, 8, 11, 5, 6, 15, 0, 3, 4, 7, 2, 12, 1, 10, 14, 9},
       {10, 6, 9, 0, 12, 11, 7, 13, 15, 1, 3, 14, 5, 2, 8, 4},
       {3, 15, 0, 6, 10, 1, 13, 8, 9, 4, 5, 11, 12, 7, 2, 14}},
      // S5
      {{2, 12, 4, 1, 7, 10, 11, 6, 8, 5, 3, 15, 13, 0, 14, 9},
       {14, 11, 2, 12, 4, 7, 13, 1, 5, 0, 15, 10, 3, 9, 8, 6},
       {4, 2, 1, 11, 10, 13, 7, 8, 15, 9, 12, 5, 6, 3, 0, 14},
       {11, 8, 12, 7, 1, 14, 2, 13, 6, 15, 0, 9, 10, 4, 5, 3}},
      // S6
      {{12, 1, 10, 15, 9, 2, 6, 8, 0, 13, 3, 4, 14, 7, 5, 11},
       {10, 15, 4, 2, 7, 12, 9, 5, 6, 1, 13, 14, 0, 11, 3, 8},
       {9, 14, 15, 5, 2, 8, 12, 3, 7, 0, 4, 10, 1, 13, 11, 6},
       {4, 3, 2, 12, 9, 5, 15, 10, 11, 14, 1, 7, 6, 0, 8, 13}},
      // S7
      {{4, 11, 2, 14, 15, 0, 8, 13, 3, 12, 9, 7, 5, 10, 6, 1},
       {13, 0, 11, 7, 4, 9, 1, 10, 14, 3, 5, 12, 2, 15, 8, 6},
       {1, 4, 11, 13, 12, 3, 7, 14, 10, 15, 6, 8, 0, 5, 9, 2},
       {6, 11, 13, 8, 1, 4, 10, 7, 9, 5, 0, 15, 14, 2, 3, 12}},
      // S8
      {{13, 2, 8, 4, 6, 15, 11, 1, 10, 9, 3, 14, 5, 0, 12, 7},
       {1, 15, 13, 8, 10, 3, 7, 4, 12, 5, 6, 11, 0, 14, 9, 2},
       {7, 11, 4, 1, 9, 12, 14, 2, 0, 6, 10, 13, 15, 3, 5, 8},
       {2, 1, 14, 7, 4, 10, 8, 13, 15, 12, 9, 0, 3, 5, 6, 11}}
  };
  private static byte K[] = new byte[64];
  private static byte M[] = new byte[64];
  private static byte MR[] = new byte[48];
  private static byte tmp[] = new byte[32];  /**
   * Type—ENCRYPT:加密,DECRYPT:解密
   * 输出缓冲区(Out)的长度 >= ((datalen+7)/8)*8,即比datalen大的且是8的倍数的最小正整数
   * Out: 加密后的数据的缓冲区
   * In: 加密前的数据的缓冲区
   * datalen: 待加密的数据长度
   * Key: 加密的密钥
   * keylen: 密钥的长度
   * type: ENCRYPT=加密; DECRYPT=解密
   */
  public static int Des_Go(byte Out[], byte In[], long datalen, byte Key[], int keylen, boolean Type) {
    if (!(Out != null && In != null && Key != null))
      return 0;
    datalen = (datalen + 7) & 0xfffffff8;
    if (datalen == 0)
      return 0;
    SetKey(Key, keylen);
    if (!Is3DES) { // 1次DES
      int p = 0;
      for (long i = 0, j = datalen >> 3; i < j; ++i, p += 8) {
        byte ob[] = new byte[8];
        byte ib[] = new byte[8];
        for (int k = 0; k < 8; k++) {
          ob[k] = Out[k + p];
          ib[k] = In[k + p];
        }
        DES(ob, ib, SubKey[0], Type);
        for (int k = 0; k < 8; k++) {
          Out[k + p] = ob[k];
        }
      }
    } else { // 3次DES 加密:加(key0)-解(key1)-加(key0) 解密::解(key0)-加(key1)-解(key0)
      int p = 0;
      for (long i = 0, j = datalen >> 3; i < j; ++i, p += 8) {
        byte ob[] = new byte[8];
        byte ib[] = new byte[8];
        for (int k = 0; k < 8; k++) {
          ob[k] = Out[k + p];
          ib[k] = In[k + p];
        }
        DES(ob, ib, SubKey[0], Type);
        for (int k = 0; k < 8; k++) {
          Out[k + p] = ob[k];
        }
        for (int k = 0; k < 8; k++) {
          ob[k] = Out[k + p];
        }
        DES(ob, ob, SubKey[1], !Type);
        for (int k = 0; k < 8; k++) {
          Out[k + p] = ob[k];
        }
        for (int k = 0; k < 8; k++) {
          ob[k] = Out[k + p];
        }
        DES(ob, ob, SubKey[0], Type);
        for (int k = 0; k < 8; k++) {
          Out[k + p] = ob[k];
        }
      }
    }
    return (int)datalen;
  }  private static void SetKey(byte Key[], int len) {
    for (int i = 0; i < 16; i++) {
      deskey[i] = 0x0;
    }
    for (int i = 0; i < (len > 16 ? 16 : len); i++) {
      deskey[i] = Key[i];
    }
    SetSubKey(SubKey[0], deskey);
    if (len > 8) {
      Is3DES = true;
      byte b[] = new byte[8];
      for (int i = 0; i < 8; i++)
        b[i] = deskey[8 + i];
      SetSubKey(SubKey[1], b);
    } else {
      Is3DES = false;
    }
  }太长,不让一次发,待续

接上:
  private static void DES(byte Out[], byte In[], byte pSubKey[][], boolean Type) {
    ByteToBit(M, In, 64);
    Transform(M, M, IP_Table, 64);
    if (Type == ENCRYPT) {
      for (int i = 0; i < 16; ++i) {
        byte Ri[] = new byte[32];
        byte Li[] = new byte[32];
        for (int j = 0; j < 32; j++) {
          Ri[j] = tmp[j] = M[32 + j];
          Li[j] = M[j];
        }
        F_func(Ri, pSubKey[i]);
        Xor(Ri, Li, 32);
        for (int j = 0; j < 32; j++) {
          Li[j] = tmp[j];
        }
        for (int j = 0; j < 32; j++) {
          M[32 + j] = Ri[j];
          M[j] = Li[j];
        }
      }
    } else {
      for (int i = 15; i >= 0; --i) {
        byte Ri[] = new byte[32];
        byte Li[] = new byte[32];
        for (int j = 0; j < 32; j++) {
          Li[j] = tmp[j] = M[j];
          Ri[j] = M[j + 32];
        }
        F_func(Li, pSubKey[i]);
        Xor(Li, Ri, 32);
        for (int j = 0; j < 32; j++) {
          Ri[j] = tmp[j];
        }
        for (int j = 0; j < 32; j++) {
          M[32 + j] = Ri[j];
          M[j] = Li[j];
        }
      }
    }
    Transform(M, M, IPR_Table, 64);
    BitToByte(Out, M, 64);
  }  private static void SetSubKey(byte pSubKey[][], byte Key[]) {
    ByteToBit(K, Key, 64);
    Transform(K, K, PC1_Table, 56);
    for (int i = 0; i < 16; ++i) {
      RotateL(K, 28, LOOP_Table[i]);
      byte b[] = new byte[36];
      for (int j = 0; j < 36; j++) {
        b[j] = K[28 + j];
      }
      RotateL(b, 28, LOOP_Table[i]);
      for (int j = 0; j < 36; j++) {
        K[28 + j] = b[j];
      }
      Transform(pSubKey[i], K, PC2_Table, 48);
    }
  }  private static void F_func(byte In[], byte Ki[]) {
    Transform(MR, In, E_Table, 48);
    Xor(MR, Ki, 48);
    S_func(In, MR);
    Transform(In, In, P_Table, 32);
  }  private static void S_func(byte Out[], byte In[]) {
    int in = 0, out = 0;
    for (int i = 0, j, k; i < 8; ++i, in += 6, out += 4) {
      j = (In[in + 0] << 1) + In[in + 5];
      k = (In[in + 1] << 3) + (In[in + 2] << 2) + (In[in + 3] << 1) + In[in + 4];
      byte b1[] = new byte[4];
      byte b2[] = new byte[1];
      b2[0] = S_Box[i][j][k];
      ByteToBit(b1, b2, 4);
      for (int m = 0; m < 4; m++) {
        Out[m + out] = b1[m];
      }
    }
  }  private static void Transform(byte Out[], byte In[], byte Table[], int len) {
    for (int i = 0; i < len; ++i) {
      Tmp[i] = In[Table[i] - 1];
    }
    for (int i = 0; i < len; i++) {
      Out[i] = Tmp[i];
    }
  }  private static void Xor(byte InA[], byte InB[], int len) {
    for (int i = 0; i < len; ++i) {
      InA[i] ^= InB[i];
    }
  }  private static void RotateL(byte In[], int len, int loop) {
    for (int i = 0; i < loop; i++) {
      Tmp[i] = In[i];
    }
    for (int i = 0; i < len - loop; i++) {
      In[i] = In[i + loop];
    }
    for (int i = 0; i < loop; i++) {
      In[i + len - loop] = Tmp[i];
    }
  }  private static void ByteToBit(byte Out[], byte In[], int bits) {
    for (int i = 0; i < bits; ++i) {
      int out = (In[i >> 3] >> (i & 7)) & 1;
      Out[i] = (byte) out;
    }
  }  private static void BitToByte(byte Out[], byte In[], int bits) {
    for (int i = 0; i < (bits >> 3); i++) {
      Out[i] = 0x00;
    }
    for (int i = 0; i < bits; ++i) {
      Out[i >> 3] |= In[i] << (i & 7);
    }
  }
  /**
   * 把加密后的数据转换成字符串，所生成的字符串只包含了从0--9和从A--F16个字符。
   * Out: 转换后的输出缓冲区, 其大小是len*2;
   * In: 待转换的数据缓冲区
   * len: 待转换的数据的长度
   */
  public static void ConvertCode(byte Out[], byte In[], int len) {
    for (int i = 0; i < len; i++) {
      Out[2*i] = ((In[i]>>4)&15) < 10 ? (byte)(0x30+((In[i]>>4)&15)):(byte)(0x37+((In[i]>>4)&15));
      Out[2*i+1] = (In[i]&15) < 10 ? (byte)(0x30+(In[i]&15)):(byte)(0x37+(In[i]&15));
    }
  }
  /**
   * 加密并转换字符
   * @param Out: 加密转换后的输出缓冲区
   * @param In: 待加密的字符缓冲区
   * @param len: 待加密的字符缓冲区的长度
   *
   * @return: 加密转换后的输出缓冲区的长度
   */
  public static int ImEncrypt(byte Out[], byte In[], int len) {
    byte key[] = {0, 2, 0, 0, 9, 3, 5, 1, 9, 8, 0, 0, 9, 1, 7, 9};
    byte buf[] = new byte[255];    for (int i=0; i<buf.length; i++) buf[i] = 0x00; //append 0x00 to tail of source    if (len == 0) {
      len = 8;
      for (int i=0; i<len; i++) buf[i] = (byte) (0x31 + i);
    } else {
      for (int i=0; i<len; i++) buf[i] = In[i];
    }
    int ret = Des_Go(buf, buf, len, key, key.length, ENCRYPT);
    ConvertCode(Out, buf, ret);
    return 2*ret;
  }  public static String ImEncrypt(String plaint) {
    String cypher = "";
    byte bPlaint[] = plaint.getBytes();
    byte bCypher[] = new byte[32];    int ret = ImEncrypt(bCypher, bPlaint, plaint.length());    cypher = new String(bCypher, 0, ret);
    return cypher;
  }  /////////////////////////////////////////////////////////////////////////////
  public static void main(String[] args) {
    byte key[] = {0, 2, 0, 0, 9, 3, 5, 1, 9, 8, 0, 0, 9, 1, 7, 9};
    byte buf[] = new byte[255];
    byte str[] = "webmaster".getBytes();    for (int i = 0; i < buf.length; i++) {
      buf[i] = 0x00;
    }
    int ret = ImEncrypt(buf, str, str.length);
    System.out.println(new String(buf));    /*for (int i = 0; i < str.length; i++) {
      buf[i] = str[i];
    }
    System.out.println("Before encrypting");
    System.out.println(new String(buf));    int len = DesEncrypt.Des_Go(buf, buf, str.length, key, key.length, ENCRYPT);
    byte out[] = new byte[len*2];
    DesEncrypt.ConvertCode(out, buf, len);
    System.out.println(new String(out));    System.out.println("After encrypting");
    System.out.println(new String(buf));    DesEncrypt.Des_Go(buf, buf, str.length, key, key.length, DECRYPT);
    System.out.println("After decrypting");
    System.out.println(new String(buf));*/
  }----------------------------
调用加密方法即可:
String encrypt = DesEncrypt.ImEncrypt(Password.trim());//

xp1204(深圳不是个好地方，我却还是要待下去) ( ) 信誉：100    Blog  2007-3-23 16:23:15  得分: 0


md5是不能解密的
自己写的就可以了

需要解密干吗?只要比较用户的密码和数据库里面是否一致,那就都加密了比较不是一样,

调试易

字段加密的问题

解决方案 »